text: 
  /*
   * Copyright (C) Igor Sysoev
   * Copyright (C) Nginx, Inc.
   */
  
  
  #include <ngx_config.h>
  #include <ngx_core.h>
  #include <ngx_event.h>
  
  
  #if (NGX_TEST_BUILD_DEVPOLL)
  
  /* Solaris declarations */
  
  #ifndef POLLREMOVE
  #define POLLREMOVE   0x0800
  #endif
  #define DP_POLL      0xD001
  #define DP_ISPOLLED  0xD002
  
  struct dvpoll {
      struct pollfd  *dp_fds;
      int             dp_nfds;
      int             dp_timeout;
  };
  
  #endif
  
  
  typedef struct {
      ngx_uint_t      changes;
      ngx_uint_t      events;
  } ngx_devpoll_conf_t;
  
  
  static ngx_int_t ngx_devpoll_init(ngx_cycle_t *cycle, ngx_msec_t timer);
  static void ngx_devpoll_done(ngx_cycle_t *cycle);
  static ngx_int_t ngx_devpoll_add_event(ngx_event_t *ev, ngx_int_t event,
      ngx_uint_t flags);
  static ngx_int_t ngx_devpoll_del_event(ngx_event_t *ev, ngx_int_t event,
      ngx_uint_t flags);
  static ngx_int_t ngx_devpoll_set_event(ngx_event_t *ev, ngx_int_t event,
      ngx_uint_t flags);
  static ngx_int_t ngx_devpoll_process_events(ngx_cycle_t *cycle,
      ngx_msec_t timer, ngx_uint_t flags);
  
  static void *ngx_devpoll_create_conf(ngx_cycle_t *cycle);
  static char *ngx_devpoll_init_conf(ngx_cycle_t *cycle, void *conf);
  
  static int              dp = -1;
  static struct pollfd   *change_list, *event_list;
  static ngx_uint_t       nchanges, max_changes, nevents;
  
  static ngx_event_t    **change_index;
  
  
  static ngx_str_t      devpoll_name = ngx_string("/dev/poll");
  
  static ngx_command_t  ngx_devpoll_commands[] = {
  
      { ngx_string("devpoll_changes"),
        NGX_EVENT_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_num_slot,
        0,
        offsetof(ngx_devpoll_conf_t, changes),
        NULL },
  
      { ngx_string("devpoll_events"),
        NGX_EVENT_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_num_slot,
        0,
        offsetof(ngx_devpoll_conf_t, events),
        NULL },
  
        ngx_null_command
  };
  
  
  static ngx_event_module_t  ngx_devpoll_module_ctx = {
      &devpoll_name,
      ngx_devpoll_create_conf,               /* create configuration */
      ngx_devpoll_init_conf,                 /* init configuration */
  
      {
          ngx_devpoll_add_event,             /* add an event */
          ngx_devpoll_del_event,             /* delete an event */
          ngx_devpoll_add_event,             /* enable an event */
          ngx_devpoll_del_event,             /* disable an event */
          NULL,                              /* add an connection */
          NULL,                              /* delete an connection */
          NULL,                              /* init a notify */
          NULL,                              /* trigger a notify */
          NULL,                              /* close a notify */
          ngx_devpoll_process_events,        /* process the events */
          ngx_devpoll_init,                  /* init the events */
          ngx_devpoll_done,                  /* done the events */
      }
  
  };
  
  ngx_module_t  ngx_devpoll_module = {
      NGX_MODULE_V1,
      &ngx_devpoll_module_ctx,               /* module context */
      ngx_devpoll_commands,                  /* module directives */
      NGX_EVENT_MODULE,                      /* module type */
      NULL,                                  /* init master */
      NULL,                                  /* init module */
      NULL,                                  /* init process */
      NULL,                                  /* init thread */
      NULL,                                  /* exit thread */
      NULL,                                  /* exit process */
      NULL,                                  /* exit master */
      NGX_MODULE_V1_PADDING
  };
  
  
  static ngx_int_t
  ngx_devpoll_init(ngx_cycle_t *cycle, ngx_msec_t timer)
  {
      size_t               n;
      ngx_devpoll_conf_t  *dpcf;
  
      dpcf = ngx_event_get_conf(cycle->conf_ctx, ngx_devpoll_module);
  
      if (dp == -1) {
          dp = open("/dev/poll", O_RDWR);
  
          if (dp == -1) {
              ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno,
                            "open(/dev/poll) failed");
              return NGX_ERROR;
          }
      }
  
      if (max_changes < dpcf->changes) {
          if (nchanges) {
              n = nchanges * sizeof(struct pollfd);
              if (write(dp, change_list, n) != (ssize_t) n) {
                  ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                                "write(/dev/poll) failed");
                  return NGX_ERROR;
              }
  
              nchanges = 0;
          }
  
          if (change_list) {
              ngx_free(change_list);
          }
  
          change_list = ngx_alloc(sizeof(struct pollfd) * dpcf->changes,
                                  cycle->log);
          if (change_list == NULL) {
              return NGX_ERROR;
          }
  
          if (change_index) {
              ngx_free(change_index);
          }
  
          change_index = ngx_alloc(sizeof(ngx_event_t *) * dpcf->changes,
                                   cycle->log);
          if (change_index == NULL) {
              return NGX_ERROR;
          }
      }
  
      max_changes = dpcf->changes;
  
      if (nevents < dpcf->events) {
          if (event_list) {
              ngx_free(event_list);
          }
  
          event_list = ngx_alloc(sizeof(struct pollfd) * dpcf->events,
                                 cycle->log);
          if (event_list == NULL) {
              return NGX_ERROR;
          }
      }
  
      nevents = dpcf->events;
  
      ngx_io = ngx_os_io;
  
      ngx_event_actions = ngx_devpoll_module_ctx.actions;
  
      ngx_event_flags = NGX_USE_LEVEL_EVENT|NGX_USE_FD_EVENT;
  
      return NGX_OK;
  }
  
  
  static void
  ngx_devpoll_done(ngx_cycle_t *cycle)
  {
      if (close(dp) == -1) {
          ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                        "close(/dev/poll) failed");
      }
  
      dp = -1;
  
      ngx_free(change_list);
      ngx_free(event_list);
      ngx_free(change_index);
  
      change_list = NULL;
      event_list = NULL;
      change_index = NULL;
      max_changes = 0;
      nchanges = 0;
      nevents = 0;
  }
  
  
  static ngx_int_t
  ngx_devpoll_add_event(ngx_event_t *ev, ngx_int_t event, ngx_uint_t flags)
  {
  #if (NGX_DEBUG)
      ngx_connection_t *c;
  #endif
  
  #if (NGX_READ_EVENT != POLLIN)
      event = (event == NGX_READ_EVENT) ? POLLIN : POLLOUT;
  #endif
  
  #if (NGX_DEBUG)
      c = ev->data;
      ngx_log_debug2(NGX_LOG_DEBUG_EVENT, ev->log, 0,
                     "devpoll add event: fd:%d ev:%04Xi", c->fd, event);
  #endif
  
      ev->active = 1;
  
      return ngx_devpoll_set_event(ev, event, 0);
  }
  
  
  static ngx_int_t
  ngx_devpoll_del_event(ngx_event_t *ev, ngx_int_t event, ngx_uint_t flags)
  {
      ngx_event_t       *e;
      ngx_connection_t  *c;
  
      c = ev->data;
  
  #if (NGX_READ_EVENT != POLLIN)
      event = (event == NGX_READ_EVENT) ? POLLIN : POLLOUT;
  #endif
  
      ngx_log_debug2(NGX_LOG_DEBUG_EVENT, ev->log, 0,
                     "devpoll del event: fd:%d ev:%04Xi", c->fd, event);
  
      if (ngx_devpoll_set_event(ev, POLLREMOVE, flags) == NGX_ERROR) {
          return NGX_ERROR;
      }
  
      ev->active = 0;
  
      if (flags & NGX_CLOSE_EVENT) {
          e = (event == POLLIN) ? c->write : c->read;
  
          if (e) {
              e->active = 0;
          }
  
          return NGX_OK;
      }
  
      /* restore the pair event if it exists */
  
      if (event == POLLIN) {
          e = c->write;
          event = POLLOUT;
  
      } else {
          e = c->read;
          event = POLLIN;
      }
  
      if (e && e->active) {
          return ngx_devpoll_set_event(e, event, 0);
      }
  
      return NGX_OK;
  }
  
  
  static ngx_int_t
  ngx_devpoll_set_event(ngx_event_t *ev, ngx_int_t event, ngx_uint_t flags)
  {
      size_t             n;
      ngx_connection_t  *c;
  
      c = ev->data;
  
      ngx_log_debug3(NGX_LOG_DEBUG_EVENT, ev->log, 0,
                     "devpoll fd:%d ev:%04Xi fl:%04Xi", c->fd, event, flags);
  
      if (nchanges >= max_changes) {
          ngx_log_error(NGX_LOG_WARN, ev->log, 0,
                        "/dev/pool change list is filled up");
  
          n = nchanges * sizeof(struct pollfd);
          if (write(dp, change_list, n) != (ssize_t) n) {
              ngx_log_error(NGX_LOG_ALERT, ev->log, ngx_errno,
                            "write(/dev/poll) failed");
              return NGX_ERROR;
          }
  
          nchanges = 0;
      }
  
      change_list[nchanges].fd = c->fd;
      change_list[nchanges].events = (short) event;
      change_list[nchanges].revents = 0;
  
      change_index[nchanges] = ev;
      ev->index = nchanges;
  
      nchanges++;
  
      if (flags & NGX_CLOSE_EVENT) {
          n = nchanges * sizeof(struct pollfd);
          if (write(dp, change_list, n) != (ssize_t) n) {
              ngx_log_error(NGX_LOG_ALERT, ev->log, ngx_errno,
                            "write(/dev/poll) failed");
              return NGX_ERROR;
          }
  
          nchanges = 0;
      }
  
      return NGX_OK;
  }
  
  
  static ngx_int_t
  ngx_devpoll_process_events(ngx_cycle_t *cycle, ngx_msec_t timer,
      ngx_uint_t flags)
  {
      int                 events, revents, rc;
      size_t              n;
      ngx_fd_t            fd;
      ngx_err_t           err;
      ngx_int_t           i;
      ngx_uint_t          level, instance;
      ngx_event_t        *rev, *wev;
      ngx_queue_t        *queue;
      ngx_connection_t   *c;
      struct pollfd       pfd;
      struct dvpoll       dvp;
  
      /* NGX_TIMER_INFINITE == INFTIM */
  
      ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                     "devpoll timer: %M", timer);
  
      if (nchanges) {
          n = nchanges * sizeof(struct pollfd);
          if (write(dp, change_list, n) != (ssize_t) n) {
              ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                            "write(/dev/poll) failed");
              return NGX_ERROR;
          }
  
          nchanges = 0;
      }
  
      dvp.dp_fds = event_list;
      dvp.dp_nfds = (int) nevents;
      dvp.dp_timeout = timer;
      events = ioctl(dp, DP_POLL, &dvp);
  
      err = (events == -1) ? ngx_errno : 0;
  
      if (flags & NGX_UPDATE_TIME || ngx_event_timer_alarm) {
          ngx_time_update();
      }
  
      if (err) {
          if (err == NGX_EINTR) {
  
              if (ngx_event_timer_alarm) {
                  ngx_event_timer_alarm = 0;
                  return NGX_OK;
              }
  
              level = NGX_LOG_INFO;
  
          } else {
              level = NGX_LOG_ALERT;
          }
  
          ngx_log_error(level, cycle->log, err, "ioctl(DP_POLL) failed");
          return NGX_ERROR;
      }
  
      if (events == 0) {
          if (timer != NGX_TIMER_INFINITE) {
              return NGX_OK;
          }
  
          ngx_log_error(NGX_LOG_ALERT, cycle->log, 0,
                        "ioctl(DP_POLL) returned no events without timeout");
          return NGX_ERROR;
      }
  
      for (i = 0; i < events; i++) {
  
          fd = event_list[i].fd;
          revents = event_list[i].revents;
  
          c = ngx_cycle->files[fd];
  
          if (c == NULL || c->fd == -1) {
  
              pfd.fd = fd;
              pfd.events = 0;
              pfd.revents = 0;
  
              rc = ioctl(dp, DP_ISPOLLED, &pfd);
  
              switch (rc) {
  
              case -1:
                  ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                      "ioctl(DP_ISPOLLED) failed for socket %d, event %04Xd",
                      fd, revents);
                  break;
  
              case 0:
                  ngx_log_error(NGX_LOG_ALERT, cycle->log, 0,
                      "phantom event %04Xd for closed and removed socket %d",
                      revents, fd);
                  break;
  
              default:
                  ngx_log_error(NGX_LOG_ALERT, cycle->log, 0,
                      "unexpected event %04Xd for closed and removed socket %d, "
                      "ioctl(DP_ISPOLLED) returned rc:%d, fd:%d, event %04Xd",
                      revents, fd, rc, pfd.fd, pfd.revents);
  
                  pfd.fd = fd;
                  pfd.events = POLLREMOVE;
                  pfd.revents = 0;
  
                  if (write(dp, &pfd, sizeof(struct pollfd))
                      != (ssize_t) sizeof(struct pollfd))
                  {
                      ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                                    "write(/dev/poll) for %d failed", fd);
                  }
  
                  if (close(fd) == -1) {
                      ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
                                    "close(%d) failed", fd);
                  }
  
                  break;
              }
  
              continue;
          }
  
          ngx_log_debug3(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                         "devpoll: fd:%d, ev:%04Xd, rev:%04Xd",
                         fd, event_list[i].events, revents);
  
          if (revents & (POLLERR|POLLHUP|POLLNVAL)) {
              ngx_log_debug3(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
                            "ioctl(DP_POLL) error fd:%d ev:%04Xd rev:%04Xd",
                            fd, event_list[i].events, revents);
          }
  
          if (revents & ~(POLLIN|POLLOUT|POLLERR|POLLHUP|POLLNVAL)) {
              ngx_log_error(NGX_LOG_ALERT, cycle->log, 0,
                            "strange ioctl(DP_POLL) events "
                            "fd:%d ev:%04Xd rev:%04Xd",
                            fd, event_list[i].events, revents);
          }
  
          if (revents & (POLLERR|POLLHUP|POLLNVAL)) {
  
              /*
               * if the error events were returned, add POLLIN and POLLOUT
               * to handle the events at least in one active handler
               */
  
              revents |= POLLIN|POLLOUT;
          }
  
          rev = c->read;
  
          if ((revents & POLLIN) && rev->active) {
              rev->ready = 1;
  
              if (flags & NGX_POST_EVENTS) {
                  queue = rev->accept ? &ngx_posted_accept_events
                                      : &ngx_posted_events;
  
                  ngx_post_event(rev, queue);
  
              } else {
                  instance = rev->instance;
  
                  rev->handler(rev);
  
                  if (c->fd == -1 || rev->instance != instance) {
                      continue;
                  }
              }
          }
  
          wev = c->write;
  
          if ((revents & POLLOUT) && wev->active) {
              wev->ready = 1;
  
              if (flags & NGX_POST_EVENTS) {
                  ngx_post_event(wev, &ngx_posted_events);
  
              } else {
                  wev->handler(wev);
              }
          }
      }
  
      return NGX_OK;
  }
  
  
  static void *
  ngx_devpoll_create_conf(ngx_cycle_t *cycle)
  {
      ngx_devpoll_conf_t  *dpcf;
  
      dpcf = ngx_palloc(cycle->pool, sizeof(ngx_devpoll_conf_t));
      if (dpcf == NULL) {
          return NULL;
      }
  
      dpcf->changes = NGX_CONF_UNSET;
      dpcf->events = NGX_CONF_UNSET;
  
      return dpcf;
  }
  
  
  static char *
  ngx_devpoll_init_conf(ngx_cycle_t *cycle, void *conf)
  {
      ngx_devpoll_conf_t *dpcf = conf;
  
      ngx_conf_init_uint_value(dpcf->changes, 32);
      ngx_conf_init_uint_value(dpcf->events, 32);
  
      return NGX_CONF_OK;
  }
  